Imagine as if you were a Imagine as if you were a pupil. Let us solve the pupil. Let us solve the

game-test. Draw physics. game-test. Draw physics. How does the radio works.How does the radio works.

The questionThe question: It explains the contents of the radio receiver (Neznayka is : It explains the contents of the radio receiver (Neznayka is wondered and begins to ask radio master, how does the sound without wondered and begins to ask radio master, how does the sound without cables reach us)cables reach us)??

The answer: the most ordinary radio receiver contains:the oscillating contour, connected with

antenna, united withchain contour, that consists of

the detectorcondensator

telephone-dynamic

The questionThe question: What is the main knot in the radio receiver, and what : What is the main knot in the radio receiver, and what can be compared with it’s in the mechanic watches?can be compared with it’s in the mechanic watches?

The answer: Represents the oscillating contour – one of he main knots of radio receiver (radio master says that the heart of radio is the contour that consists of inductive spool and condensator).

The question: The question: What is the condensator, and how does it charge?What is the condensator, and how does it charge?

The answer: The condensator consists of two conductors, divided by the layer of isolator, which thickness is small in compare with conductor’s size. To charge the condensator we have to join it’s conductors with the generator’s poles. The plates charges are similar in the count meaning, but opposite by the sign. This is the image expression of the condensator’s charging process. The signs on it’s sides mean hoarded charges.

The question: The question: how does the oscillating contour works?how does the oscillating contour works?

The answer: By the condensator’s spacing through the inductive spool, in the created chain the electric oscillations appear. In the process of these oscillations goes the periodic transformation of the energy of the electric field in the energy of the magnetic field and inversely. It explains how the oscillating contour acts (the mechanism of its «swinging»).

The question: The question: Thanks to what natureThanks to what nature phenomenon the distant radio phenomenon the distant radio connection goes?connection goes?

The answer: 1) thanks to short waves from 10m to 100meters, that spread on long distances only by frequent reflections from

the ionosphere and the surface of the Earth, it is possible to realize the radio connection on every distance between the

radio stations on the Earth.2) On the limited distances the connection is realized on long

waves, longer than 100meters.3) On the distances of the direct evidence and for the

connection with the space ships the extremely short waves are used, they are less than 10m.

The fifth picture represents the multitude of radio waves that «entangle» the Earth.

The question: The question: What is called the resonance?What is called the resonance?

The answer: The phenomenon of the forced oscillations’ amplitude rough increasing by the equality of the forcing power frequencies and the personal oscillating system frequency is called the resonance. The sixth picture explains the phenomenon of mechanical resonance (each harp’s string responses it’s personal sound).

The question: The question: How can we tune the radio receiver on the necessary wave?How can we tune the radio receiver on the necessary wave?

The answer: The seventh picture helps to understand the process of oscillating contour tuning in the resonance with the definite wave (we roll the condensator’ knob and change the inductive spools: we attain so that the personal frequency of contour coincides with the frequency of the necessary radio station wave. The contour doesn’t permit: their frequency is not that one and they are «unnecessary»).

The question: The question: What wave reforms are represented on this picture?What wave reforms are represented on this picture?

The answer: the eighth picture illustrates the transformation of sound waves in the oscillations of the electric current and inversely

The ninth picture acquaints us with the process of wave The ninth picture acquaints us with the process of wave modulation.modulation.The question: The question: What is called the modulation process? What is called the modulation process?

The answer: Modulation–is the change of the high frequency oscillations (the carrying frequency of the electric-magnetic

waves) with help of low (sound) frequency electric oscillations in the oscillation amplitude.

the graphic of the high frequency oscillations. Such frequency is called the carrying frequency.

the graphic of the sound frequency oscillations, i.e. modulating oscillations.

the graphic of the oscillations, modulated in the amplitude.

The question: The question: What electric-magnetic wave is demonstrated?What electric-magnetic wave is demonstrated?

The answer: the tenth picture acquaints with modulated wave.

The question a: The question a: What is called the detectionWhat is called the detection??

The question b: The question b: Tell about detection through the illustrationTell about detection through the illustration..

The answer a: the allotting of the low frequency oscillations from the modulated high frequency oscillations. The signal, got in the result of detection, matches the sound signal, that influenced on the transmitter microphones. The eleventh picture is the analogy of the received electric-magnetic waves detection (the man, named The Detector – D, chops with an axe the negative semi-periods of the received radio waves).The answer b : the twelfth picture gives the presentation of the process of modulated oscillations dividing into high frequency and low frequency oscillations; for high frequency oscillations as the analog the Mother is imagined, for low frequency oscillations – the child; therefore the modulated oscillations are presented by us (from the right) as the flow of women-passengers carrying their children; in the building of the railway station D (detector) the flow dividing goes: the children (low frequency oscillations) continue their way straightly, but mothers (high frequency oscillations) turn into the perpendicular platform.

The question: The question: What can be said about the radio waves percolation What can be said about the radio waves percolation possibilities? Which of the listeners: a man, sitting in the open area or a possibilities? Which of the listeners: a man, sitting in the open area or a man, sitting in the ferro-concrete building – has the better radio wave man, sitting in the ferro-concrete building – has the better radio wave receiving?receiving?

The answer: The better radio waves receiving has the man, sitting in the open area. The man in the building has more feeble receiving,

because the radio wave has some attributes: the absorption by different isolators.

the reflection from different metal plates.the refraction on the boundary of isolator.

The thirteenth picture shows the permeation ability of radio waves.